Interpretive Summary: Maintaining the productivity of soil is essential in sustaining crop yields and adequate vegetative cover, as well as in supporting a variety of ecosystems. In particular, surface soil is an important natural resource and areas that are susceptible to surface soil erosion face the potential problem of decreased crop productivity and diminished water quality. Thus, the assessment of soil erosion sensitivity, such as conducted in this study, can serve as a primary data source with the aim of controlling soil erosion and achieving environmental sustainability. This research, incorporating the use of remote sensing and GIS technologies, indicates that natural factors such as precipitation, soil, topography and vegetation in the Tongbai-Dabie mountainous area of China have a significant influence on the distribution of soil erosion sensitivity. The results of this study show that precipitation is the dominant factor that affects the distribution of soil erosion sensitivity in the study area. Through comprehensive assessment of soil erosion sensitivity, we found that the soil erosion sensitivity in the study area was relatively high. Results demonstrate that areas of moderate to extreme sensitivity account for 46.34% of the total area, while mild sensitivity and insensitive areas account for 44.30% and 9.36%, respectively. Considering the pattern of spatial distribution, sensitivity analyses indicated lesser potential of erosion occurring from north to south with the most sensitive regions found mainly in the south and central areas of the hilly counties in Jinzhai, Huoshan, Yuexi, Shucheng, Shangcheng, while less sensitive regions were located in the northern plains. The outcome from sensitivity analyses and adverse human activities dictate the unsustainability of the eco-environment for a given area. While natural factors are the underlying conditions of the development and occurrence of soil erosion, human activities tend to exacerbate soil erosion. Considering natural factors, vegetation is the primary factor influenced by human activities. Therefore, altering inappropriate land use management, returning farmland to native forest, remediating commercial forest on hillslopes, and strengthening the protection and reconstruction of vegetation are key measures that should be taken to control and prevent soil erosion now and in the future within this region.

Technical Abstract:
Soil erosion reduces crop productivity and creates negative impacts on water quality. Soil erosion by water has become a problem worldwide and as concerns about the environment continue to grow, soil erosion remains a very active area of scientific research. In this study, based on advanced remote sensing and GIS technologies, the influences of precipitation, soil, topography and vegetation on soil erosion sensitivity are evaluated. An index system and classification standard for soil erosion sensitivity assessment in the Tongbai-Dabie Mountainous area are established to determine different levels of soil erosion sensitivity in order to provide a scientific basis for controlling soil erosion and making sound ecological engineering decisions. According to the regional conditions, sensitivity is classified into five levels: insensitive, mild, moderate, high and extreme. The distribution of erosion sensitivity for the region is analyzed and the various impacts are discussed. The results show that the sensitivity of the Tongbai-Dabie Mountainous area to soil erosion is relatively high, with 46.34% of the total area above the moderate level, and 44.30% and 9.36% rated at the mild and insensitive levels, respectively. In regards to the spatial distribution, the sensitivity levels decrease from south to north, with highly sensitive areas found mainly in the south in the areas of Jinzhai, Huoshan, Shangcheng, Yuexi, and Shucheng. The distribution of soil erosion sensitivity levels was very consistent with the intensity of soil erosion. Areas of high sensitivity are found to have severe areas of soil erosion, indicating that regional soil erosion is highly influenced by natural factors, although in some areas it is evident that the impact of human activities has played a significant role in exacerbating the problem. The results of this investigation serve to advance efforts to reduce the impacts soil erosion in the region and prevent further erosion in areas having high erosion sensitivities.